* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    min-height: 100vh;
    position: relative;
    padding-bottom: 100px;
    box-sizing: border-box;
}

footer{
    padding: 10px 10px;
    position: absolute;
    bottom: 0;
    width: 100%;
    text-align: center;
}